Welcome back to the First We Feast GIF Tutorial series, where we ask restaurant cooks and pro bartenders to show us how step up our technique when cooking and making drinks at home.

You can buy all manner of ridiculous cooking devices from Sky Mall, drop thousands of dollars on a sous-vide machine, and get fancy ingredients galore, but if you really want to become a better cook, the key is to learn the fundamentals that will serve as building blocks for every dish you make.

One of those fundamentals is the classic roux: a simple, equal-parts blend of fat (usually butter, though you might use oil or lard) and flour that serves as one of the lynchpins of French cuisine. It’s used to thicken sauces and give them an extra oomph of fatty flavor—cook a roux with milk, onions, and spices, and you’ve got a textbook béchamel. Combine it with stock and you’ve got a velouté, another of the famed “mother sauces,” and one that’s ideal for soups.

After he showed us how to cook a perfect steak, we asked Atera sous chef Zach Hunter to take use through the steps of roux-making. Turns out it’s pretty damn easy, but it’s a crucial skill to master, and there are a few rookie mistakes to avoid.

One important note: Here, Hunter makes a white roux, which is when the flour is barely cooked; it’s what you would use in a béchamel (and, by extension, a real-deal mac and cheese). The other two types—blond and brown—are made exactly the same way, they’re just a cooked longer; blond roux takes 10 to 20 minutes and has the aroma of cooked nuts, while brown roux can take up to 30 minutes and will have an even richer aroma. The key to making a roux is simple: Use low heat and stir a lot to avoid burning the butter—once it burns, there’s not much you can do to mask the bitter taste.

Now, whenever you see a recipe that begins “make a roux,” you won’t have to mess around.

Click through the gallery above to see Hunter demonstrate each step of the roux process.